S38 on E30 rev counter problem

[grehur]

Hi Everybody,
Please excuse my english... but I have a small problem and I need your help.
I've done an engine swap on my E30 (1986), I have now S38 3.8L. Everything is ready except the rev counter, wich I can't get it to work, because the rev signal on M5 comes from the ecu and in my E30 originally doesn't.
How can I solve this?
regards
G

[JoeMadoo]

you can wire the RPM signal wire from the ecu to the 3-pin c104 connector also in your glove box. i think it's the black wire.

[StereoInstaller1]

Yes on both.

If you had a 6 cylinder car the coding plug on the tachometer should be the same.

[Jb325is]

Don't know the answer to your question, sorry, but does your plenum hit your brake booster? Which plenum are you running? I just bought some s38 throttle bodies for my car and I think this is going to be an issue.

I guess what I'm really saying is: Pics please!! :)

[grehur]

I have no pics yet because the car is still at the shop ... but I'll go there and take some for you.

thanks for the tips on solving the problem

regards

G

[grehur]

Regarding the brake booster, stock would not fit, so I bought a smaller one. I'll take pictures for you to see

[Jb325is]

Regarding the brake booster, stock would not fit, so I bought a smaller one. I'll take pictures for you to see

This is the info I was looking for, please let me know which one you used, VW? You should definitely post pictures though, not many s38 swaps on here

Regarding your question, I'm guessing since it's a 3.8 you used a 25 pin harness? Search for threads started by Jean, he did a lot of work decoding the e34 25 pin harness that may help you out.

[Jean]

Instead of using a VW booster, why not move the booster behind the headlight like on the 530/540 cars? Still no room?

[grehur]

My brake booster is from a ... lol.. citroen saxo... :-) It's the best fit with minimum changes :-) I've not tried it yet, but next week I hope everything is ok and I'll try it and post here.

[Alpina]

, sorry, but does your plenum hit your brake booster? Which plenum are you running? I just bought some s38 throttle bodies for my car and I think this is going to be an issue.

I guess what I'm really saying is: Pics please!! :)

oem E34 M5 booster + master drilled/slided the hole 1/2 an " to the left,, it is narrow but works superb